In solid modeling, a “part” can consist of individual features. An example of a feature is a base of the part. The base is the feature on which a design engineer creates additional features. The base feature can be the result of an extrusion, a revolve, a sweep, a loft, a thickening of a surface, or a sheet metal flange, for example. Most commonly base features result from an extrusion operation in solid modeling.
An extrusion operation creates a feature by extruding a 3D object from a 2D sketch, essentially adding the third dimension. An extrusion that forms a base always adds material. An extrusion that forms a boss adds material, often on another extrusion. An extrusion that forms a cut removes material. A revolve, or revolution, operation creates a feature by revolving one or more sketch profiles about a centerline to add or remove material. The feature can be a solid, a thin feature, or a surface. A loft operation creates a feature by making transitions between profiles. A loft can form a base, boss, cut, or surface. A sweep operation creates a base, boss, cut, or surface by moving a profile (section) along a path. A boundary operation creates high quality, accurate features useful for creating complex shapes for the consumer product design market, the medical market, the aerospace market, and the mold market. A boundary can form a base, boss, cut, or surface.
Features can be either sketched features and/or applied features. Sketched features are based on sketch geometry. Sketched features can include extrusions, revolves, sweeps, and lofts. Applied features are features applied directly to the model. Applied features include chamfers, fillets, and shells.
Features are suited to be added to the model, whether the feature adds or removes material to or from the model. In many history-based modelers, for a given part, the model stores a history of features added, so that the design engineer can modify features after creation. Some solid modelers, however, do not store the history of features added. After the part is created, a design engineer can use a tool, (e.g., the SolidWorks Defeature tool) to remove feature-based details from a part or assembly and save the results to a new file in which the feature-based details are replaced by a “dumb solid.” The “dumb solid” is a solid model without the feature definitions or history.
Motion studies are simulations of motion for assembly models, and can include graphical simulations or simulations of physical properties such as velocities and forces. A design engineer can incorporate visual properties such as object movement, lighting and/or camera perspective into a motion study. Motion studies do not change an assembly model or its properties, but rather simulate and animate motion that the design engineer prescribes for a model. The design engineer can employ SolidWorks mates to restrict motion of components in an assembly when modeling motion. The design engineer can use mates to restrict motion between components for motion studies. The design engineer can, for example, set the values for distance and angle mates, and change these values for different points in an animation. For example, the design engineer can add an angle mate to restrict the position of a first component to 30°. The design engineer can also use a motion study to animate the change in behavior of components when the value of the mate between two components incrementally changes from 15° to 45° over a period of time so the component moves accordingly.